What is a Certificate of Engineering?
Most jewellers ask you to trust them. We would rather hand you the measurements. Every Zefire piece ships with a document recording exactly what it is made of, and exactly how closely it matches the design it was made from.
What is a Certificate of Engineering?
A Certificate of Engineering is a document issued with every Zefire piece that records what the piece is physically made of and how precisely it matches the design it was made from. It contains the gold composition verified by X-ray fluorescence, a unique serial number for that individual piece, the ATOS 3D scan data comparing the finished item against its original CAD model, and its net and gross weights.
It is not a valuation or an appraisal. It is a measurement record — the same kind of document a precision manufacturer issues for a component, applied to jewellery.
What is engineered jewellery?
Engineered jewellery is jewellery designed and verified using the tolerances and measurement methods of precision manufacturing rather than the conventions of craft alone. In practice that means the finished piece is measured against its design file, deviations are recorded rather than estimated, and the result is documented.
Traditional fine jewellery is judged by eye and by the maker's reputation. Engineered jewellery is judged by instrument and recorded in numbers. Both can be beautiful; only one can be checked.
What is an ATOS 3D scan and why does it matter for jewellery?
ATOS is an optical 3D measurement system mounted on a robotic arm, used by Swiss watch manufacturers and aerospace suppliers to verify critical components. Zefire uses one in its Delhi studio to scan finished pieces and compare them against the original CAD model, producing a full-surface deviation map rather than a handful of spot checks.
On jewellery it matters because tolerance is what you feel rather than what you see. A ring whose inner surface deviates by a fraction of a millimetre is the difference between one that sits comfortably all day and one you keep adjusting.
How do I know the gold purity is what it claims?
Two independent checks. Every Zefire gold piece carries a BIS hallmark, which is the Government of India's certification of purity, applied by a licensed assaying centre rather than by us. Separately, the composition is X-ray tested in-house and that reading is printed on the Certificate of Engineering with the piece's serial number.
A hallmark tells you the piece passed. The certificate tells you the actual measured figures.
Is a Certificate of Engineering the same as a diamond certificate?
No, and both are supplied where relevant. A diamond certificate from IGI or GIA grades the stone — cut, colour, clarity and carat — and is issued by an independent gemmological laboratory. The Certificate of Engineering covers the piece as a manufactured object: its metal composition, its dimensional accuracy against the design, and its serial number.
One certifies the stone. The other certifies the thing the stone was set into.
Where is Zefire jewellery made?
Zefire is designed in London and manufactured in its own studio in New Delhi, India. Design, casting, setting, finishing and 3D verification all happen in-house rather than being outsourced, which is what makes it possible to scan and document every piece rather than a sample.
